Re: Linux 2.6.38-rc5

[Eric Dumazet <eric.dumazet@gmail.com>]

Le mercredi 16 février 2011 à 12:14 +0100, Eric Dumazet a écrit :
> Le mardi 15 février 2011 à 20:16 -0800, Linus Torvalds a écrit :
> > Another week, another -rc.
> > 
> > Nothing much stands out here - we've fixed some regressions
> > (including, hopefully, a BUG_ON() due to the new RCU filename lookup
> > that Ubuntu people saw), and things look fairly normal.
> 
> Using this kernel on my dev machine (2x4x2 cpus), I hit BUG_ON() in
> fs/namei.c:1461 on my kernel build (make -j16)
> 
> BUG_ON(inode != next.dentry->d_inode)
> 
> I do have DEBUG_PAGEALLOC and LOCKDEP on
> 
> 

Since I hit this BUG_ON() even on boot, I spent some time tracking it.

I bisected the problem to commit 844a391799c25d9b
(nothing in do_follow_link() is going to see RCU)

Reverting this commit makes my machine happy again.

My filesystems are ext3

# mount
/dev/sda2 on / type ext3 (rw)
none on /proc type proc (rw)
none on /sys type sysfs (rw)
none on /dev/pts type devpts (rw,gid=5,mode=620)
usbfs on /proc/bus/usb type usbfs (rw)
/dev/sda6 on /appli type ext3 (rw)
/dev/sda1 on /boot type ext3 (rw)
none on /dev/shm type tmpfs (rw)
/dev/sda7 on /opt type ext3 (rw)
/dev/sda3 on /var type ext3 (rw)
none on /sys/kernel/debug type debugfs (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)